The future of the Colombo crime family — an 83-year-old operation that once ruled New York’s waterfront and has been the most bloodthirsty of the city’s five Mafia families — rests with two little-known brothers-in-law who secretly recorded their bosses for months.

Tommy McLaughlin and Peter Tagliavia were exactly the kind of up-and-coming associates needed to retool the once-proud Colombos: young, tough, prison-tested and ambitious. Each had survived shootouts during the family’s brutal internal war in the 1990s, which decimated the clan. Each was considered a stand-up guy.

Instead, they and a third turncoat, Frankie “Blue Eyes” Sparaco, have helped bring down the entire leadership of the Colombos, including former street boss Thomas “Tommy Shots” Gioeli, who was busted last year and faces murder and racketeering charges, and the man who took over that role, Andrew “Andy Mush” Russo.

McLaughlin, 41, is Gioeli’s nephew and provided particularly damaging evidence, having flipped after getting out of jail following a 14-year stint, only to face life when hit with fresh murder charges.

“He didn’t want to go back to prison, not after doing all that time behind bars with nothing to show for it,” a source told mob chronicler Jerry Capeci, who broke the story of McLaughlin’s cooperation on GanglandNews.com.

On Jan. 20, as the feds launched the biggest one-day arrest of gangsters ever, McLaughlin and Tagliavia were being whisked off to safety — a potential kill shot to the battered Colombos, whose underboss Benjamin “The Claw” Castellazzo, and consigliere Richard “Ritchie Nerves” Fusco, also got locked up. All told, 34 members were busted, including four captains and eight soldiers.

The arrests left the family with less than half the made members it had just five years ago, perhaps as few as 40 to 50 full-fledged wiseguys walking the streets. That makes it by far the smallest of the five crime families — and probably smaller than even New Jersey’s equally ravaged DeCavalcante clan.

“They did it to themselves,” one law-enforcement source said, noting that a parade of well-placed informants systemically sold out their fellow mobsters since 2005.

The Colombos can still draw on veteran mafiosi like longtime boss Carmine Persico, who continues to call the shots from jail, but there’s just one Persico relative who is not in prison or dead, Danny Persico, a minor figure who lives on Long Island.

Everyone else is six feet under or locked up.

“There’s nobody left,” said a veteran investigator. “The old-timers are too old and too tired. There are still big moneymakers who bring in tons of cash, but they’re not combatants. They are not involved in homicides. To run things, you need somebody who has two sides to him.”

If this is, in fact, a requiem for the Colombos, they leave behind a brutal legacy, filled with the most colorful characters in gangland lore, a legendary band that inspired fictional depictions ranging from “On the Waterfront” to “The Gang That Couldn’t Shoot Straight.”

Among its notable goodfellas were Joseph “Crazy Joe” Gallo, who terrorized foes with a mountain lion he kept in his Red Hook basement; William “Wild Bill” Cutolo, a stone-cold hit man who donned a Santa outfit each Christmas and bounced sick kids on his knee; and Gregory “Grim Reaper” Scarpa, of whom Brooklyn prosecutor Michael Vecchione said, “There’s nobody like him in the history of the mob.”

Scarpa, a violent thug who rose to the rank of capo, had a special relationship with the FBI, which enlisted his help to solve the “Mississippi Burning” murders of two civil-rights workers in 1964 — and allegedly looked the other way while he committed crimes. In exchange, he secretly served as informant for 35 years.

Ironically, this thing of theirs started with a legitimate business.

THE Colombos, the last Cosa Nostra family to be formally organized when they came together in 1928, were started not by a Colombo but rather by import entrepreneur Giuseppe “Joe” Profaci, a Sicilian-born Brooklynite whose company Carmela Mia was once the largest distributor of olive oil and tomato sauce in the United States. His nickname was “The Olive Oil King.”

But he was also known for less savory contributions: gambling, extortion, hijacking, prostitution, protection rackets and a new specialty, squeezing labor unions, a reliable and ongoing source of income from the time Profaci became a charter member of the mob’s ruling commission in 1931.

Profaci, who lived in a mansion on a sprawling spread in Bensonhurst, eagerly embraced the drug trade, importing heroin through hollow wax oranges. He battled the IRS his entire life and attended the infamous Apalachin Conference, busted up by New York state troopers in 1957, but he never did time.

Among his domain was South Brooklyn’s waterfront, a collection of bustling docks where tough guys who could have been contenders often worked for the family collecting debts or snatching cargo.

The only real challenge he faced came in 1960, when hotheaded soldier “Crazy Joe” Gallo, his two brothers, and ally Carmine Persico kidnapped Profaci’s handpicked successor — his brother-in-law Joseph Magliocco — and a supporter, Joseph Colombo, in retaliation for being denied a bookmaking racket.

The hostages were all let go after intense negotiations, during which the boss quietly convinced Persico to switch sides and join him.

When Profaci died from liver cancer in 1962, he had ruled for more than three decades — though he was despised by much of the family, for forcing every last one of them to pay him a tithe and murdering those who complained.

Magliocco then took over, but not for long. He was forced out by the commission for plotting with Joe Bonanno to kill rival bosses Tommy Lucchese and Carlo Gambino.

The ill-fated scheme came to light after Magliocco ordered Colombo to do the hits and Colombo promptly told his targets instead of offing them. The deposed boss died of a heart attack in 1963, and the other families supported Colombo as the new family leader.

They would regret it.

The family took his name, and Colombo became the Mafia’s first media star, raging at the FBI after agents arrested his son in 1970. He turned the beef into a crusade, organizing marches in front of the bureau’s headquarters and casting its crackdown as an affront to Italian-American civil rights.

The attention brought increased FBI scrutiny, infuriating Gambino and other bosses. At a rally in Columbus Circle in 1971, an assassin pumped three bullets into Colombo’s head, rendering him “vegetabled” in Crazy Joe’s words. He clung to life until 1978 but never regained consciousness.

The shooting thrust the family into a rudderless era as a succession of bosses and acting bosses assumed and relinquished the throne. The strongest of them was Persico, who exacted revenge on Gallo soon after his old rival got out of prison.

Crazy Joe was celebrating his birthday at Umberto’s Clam House in Little Italy in 1972 when gunmen opened fire on the party. The rubout became one of the most notorious in Mafia history.

But Persico — nicknamed “The Snake” because he once crawled out from under a car to rub out a rival — could not slither away from investigators and was sentenced to 100 years in 1986. He would remain boss but planned to pass day-to-day management to his son, Alphonse “Little Allie Boy,” who was due to get out of jail two years later. In the meantime, capo Vic Orena got the job on an interim basis.

Persico’s best-laid plans went belly-up. When Allie Boy got out, Orena refused to step down — and a brutal and bloody war ensued.

The battle wouldn’t end for two more years, during which 12 people were killed, including two innocent bystanders. Many were injured and scores of mobsters went to jail. The Persico faction eventually prevailed but at a huge cost to the family.

“I don’t think they’ve ever recovered,” said Brooklyn prosecutor Vecchione, who handled many of the cases against the Colombos. “There have been factions in other families, but nothing to this extent. The number of murders and the mayhem was unprecedented.”

The episode’s central character was Scarpa, who did the most shooting and once bragged, “I love the smell of gunpowder.”

“The guy thought he was James Bond,” marveled Vecchione. “He told his kids he worked for the government.”

Scarpa and his common-law wife, Linda Schiro, worked together and shared a longtime ménage-à-trois affair with former delivery boy Larry Mazza, whom Scarpa turned into a valuable hit man.

His FBI handler, Lindley DeVecchio, was indicted in 2006 for allegedly helping Scarpa carry out four gangland killings, but the Brooklyn DA’s office dropped the case when tapes emerged in which Schiro contradicted herself.

WHAT will happen to them now?

Following the crackdown headed by a 10-agent FBI team headed by veteran Colombo squad supervisor Seamus McLearney, rumors of the family’s demise might not be exaggerated. There has long been talk of carving up the clan and spreading its members to the other four families.

Certainly, there are valuable pieces left.

The Colombos continue to exert control over the cement and concrete workers union, Local 6A. “You can’t put a dollar figure on that,” said one law-enforcement source. “And there’s a lot of loan-sharking, which is extremely profitable.”

But there’s always a chance they’ll scurry away to rob another day. There are some capable captains — namely, Ralph Lombardo and William Russo, the son of jailed boss Andrew “Andy Mush” Russo.

There’s a telling sign of how even when law enforcement thinks it has the mob cracked, there are still mysteries. Investigators don’t know how Russo, now 76, got his nickname.